Although boiling process has been a major subject of
research for several decades, its physics still remain unclear and require
further investigation. This study aims at highlighting the effects of
surface wettability on pool boiling heat transfer. Nanocoating techniques
were used to vary the water contact angle from 20 to 110° by modifying
nanoscale surface topography and chemistry. The experimental results
obtained disagree with the predictions of the classical models. A new
approach of nucleation mechanism is established to clarify the nexus between
the surface wettability and the nucleate boiling heat transfer. In this
approach, we introduce the concept of macro- and micro- contact angles to
explain the observed phenomenon.